With vigorous development of internet applications, the existing 3 Generation (3G) communication network can not meet the growing demand. Wireless communication systems are increasingly taking development trends of mobility, broadband and internet. Under this circumstance, as the 4 Generation (4G) communication technology, 3GPP Long Term Evolution (LTE) becomes the future network evolution direction.
LTE network is based on the full Internet Protocol (IP) architecture, and can only provide Voice over IP service (VoIP) based on Packed-Switched (PS). As LTE network does not possess capabilities of calling and service controlling needed in conversation services, it is therefore required for IP Multimedia Subsystem (IMS) of a core network to provide the control function needed in the conversation service.
Deployment of LTE network and IMS network is a gradual process. At the beginning of constructing a LTE network, to ensure a connection among voice services, an implementation approach provides a mobile communication terminal having dual-standby ability. For example, the mobile communication terminal may standby simultaneously in a LTE network and a 2G/3G network, which is referred to as Simultaneous Voice and LTE (SVLTE).
Inventors of the present disclosure have found through researches that the conventional mobile communication terminal having dual-standby ability has some drawbacks, such as big size, high cost and difficult to design.
The drawbacks mainly result from the fact that, if receiving simultaneously both LTE system signal and 2G/3G system signal, the mobile communication terminal needs at least three antennas, wherein two antennas are dedicated to LTE system, and one antenna is dedicated to 2G/3G system.
In other words, with respect to a mobile communication terminal having single-standby ability, the mobile communication terminal having dual-standby ability requires additional antennas, RF chips, filters, and even baseband chip, and thus resulting in high R&D difficulty and long cycle.
Furthermore, with respect to a mobile communication terminal with single-standby ability, the mobile communication terminal with dual-standby ability may have an increased size of printed circuit board. However, middle and low-end mobile communication terminals on the market generally have a screen size of 4.0″ and even smaller, which brings challenges in the design, especially for manufacturers demanding for strict design requirements.